CSharpNotificationCenter Posting Messages with data

for me this solution worked:

 * Example use Post Notification / AddObserver with data:
  * 
  * 1) Example use Post Notification:
  * 
     // Post Notification with data:
     Hashtable hashtable = new Hashtable();
     hashtable.Add("attribute1", 1000);
     hashtable.Add("attribute2", 55);    
     NotificationCenter.DefaultCenter.PostNotification(this, "OnBumperCollision", hashtable);
  * 
  *  2) Example AddObserver and reuse posted data of Notification:
  * 
     using UnityEngine;
     using System.Collections;
     public class testObserveB : MonoBehaviour {
         void Start () {
             NotificationCenter.DefaultCenter.AddObserver(this, "OnBumperCollision");
         }
         void OnBumperCollision (Notification note)
         {
             Debug.Log("OnBumperCollision detected!");
             // reuse data if it exists
             if (note.data!=null) {
                 Debug.Log("Sender="+note.sender.name);
                 Debug.Log("Data:");
                 foreach (DictionaryEntry entry in note.data)
                 {
                     Debug.Log(" "+entry.Key +"="+ entry.Value);
                 }
             } else {
                 Debug.Log("data is null.");
             }
         }    
     }

but befor this can work, the Notification class must be accessible from outside:

     public class Notification {
      
             //public Notification (GameObject aSender, string aName, Hashtable aData)
             //{
             //    throw new System.NotImplementedException ();
             //}
      
         public Component sender;
         public string name;
         public Hashtable data;
         public Notification (Component aSender, string aName) { sender = aSender; name = aName; data = null; }
         public Notification (Component aSender, string aName, Hashtable aData) { sender = aSender; name = aName; data = aData; }
      
      
     }

this was not the case with the script in the wiki...

To send/access a notification's data parameter you must first send some data along with your notification:

 NotificationCenter.DefaultCenter.PostNotification(this, "OnPlayerEnter", someVectorThree);

Then:

 void Start()
     {
         NotificationCenter.DefaultCenter.AddObserver(this, "OnPlayerEnter");
     }
 
 void OnPlayerEnter(NotificationCenter.Notification note)
     {
         Vector3 someVectorThree = note.data;
     }

I never used this script, but it looks like of a custom implementation of delegates, which are supported by Unity. I would like to know the advantage of using this script instead of built-in delegates (after my first read of the community page I didn't see any).

See: delegate (C# Reference) and Delegates (C# Programming Guide)

See also: Delegates Tutorial

edit: I think that the receiving method should have this kind of signature:

 void MethodName(object arg)
 {
     // cast inside the method
     Hashtable hash = arg as Hashtable;
     if (hash == null)
     {
         // error
     }
 }

But I'm not sure since I never used Unity built-in messaging system (which is the final step of this implementation).

 public class Notification {
  
     public Component sender;
     public string name;
     public Hashtable data;
     public Notification (Component aSender, string aName) { sender = aSender; name = aName; data = null; }
     public Notification (Component aSender, string aName, Hashtable aData) { sender = aSender; name = aName; data = aData; }
  
  
 }